Such a double flywheel is described in the French published patent application No. FR 2 593 871A, which describes damping means in which friction rings comes into operation as from the commencement of the relative angular movement between the masses. This arrangement cannot be entirely satisfactory, especially in respect of the effective removal of dead point noises when the engine of the vehicle is running in a decelerating mode. This is because the friction cannot be made as small as is desirable.